/*
 * gybon - Core modules for Google Yahoo Rich Application Framework
 *
 * Copyright (c) 2009, Yves Cuillerdier
 * All rights reserved.
 * 
 * This software is licensed under the new BSD License:
 * 
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, 
 * this list of conditions and the following disclaimer.
 * 
 * Redistributions in binary form must reproduce the above copyright notice, 
 * this list of conditions and the following disclaimer in the documentation 
 * and/or other materials provided with the distribution.
 * 
 * Neither the name of the author nor the names of its contributors may 
 * be used to endorse or promote products derived from this software without 
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * @version 0.2.0
 */
package gyraf.wrapper.client.misc;

import com.google.gwt.core.client.JavaScriptObject;

/**
 * Utility method to define colors in Html format
 */
public final class HtmlColor {

	private final int red;
	private final int green;
	private final int blue;

	private final String[] lookup = { "0", "1", "2", "3", "4", "5", "6", "7",
			"8", "9", "a", "b", "c", "d", "e", "f" };

	/**
	 * Create an Html color.
	 * 
	 * @param r
	 *            red value
	 * @param g
	 *            green value
	 * @param b
	 *            blue value
	 */
	public HtmlColor(final int r, final int g, final int b) {
		red = r % 256;
		green = g % 256;
		blue = b % 256;
	}

	/**
	 * Get the color as an #rrggbb value
	 * 
	 * @return the #rrggbb color
	 */
	@Override
	public String toString() {
		return "#" + hex(red) + hex(green) + hex(blue);
	}

	private String hex(final int v) {
		final int l = v % 16;
		final int h = v - 16 * l;
		return lookup[h] + lookup[l];
	}

	/**
	 * get the color as a JavaScript array [ r, g, b]
	 * 
	 * @return a JavaScript array [ r, g, b]
	 */
	public native JavaScriptObject toJsArray() /*-{
		return [this.@gyraf.wrapper.client.misc.HtmlColor::red, this.@gyraf.wrapper.client.misc.HtmlColor::green, this.@gyraf.wrapper.client.misc.HtmlColor::blue];
	}-*/;
}
